Zalman VF1000 LED Graphics Card Cooler

The first step in our testing was to see how the X1950XTX's
stock cooler performed. It consists of a copper base connected to a group
of fins by only a single heatpipe. The fan acts as a blower, pushing air
over the fins out the exhaust grill. The unit is covered with a plastic
shroud which prevents air from being expelled elsewhere.

The X1950XTX and stock cooler.

The stock cooler's underside.

ATI Tool's Fan Control settings.

According to ATI Tool, the fan ramps up in speed depending on the temperature
reported by the thermal sensor. We were unsure what fan speed to use so we
did a bit of informal initial testing. When left on default settings, the
fan ran at 12% speed when idle and on load, the temperature stabilized in
the low 80's with the fan alternating between 38% and 56% speed. 56% was very
loud and at 38% the load temperature rose above 95°C, so to compromise
we set it at 43% for testing. At this setting it wasn't loud enough for us
to want to tear our hair out and the load temperature was more acceptable.
We tried to set it at 40% but apparently the next step above 38% it would
accept was 43%.

X1950XTX Stock Cooler Test Results

State

Fan Speed

GPU Temp

VGA Ambient

CPU Temp

AC Power

System Noise @ 1m

ATI Tool

43%

85°C

67°C

40°C

253W

32 dBA

Idle

12%

71°C

55°C

25°C

130W

22 dBA

At 43% the noise signature was smooth but overall was quite loud. Anything
higher sounded like a small engine or vacuum. At 13% the fan emitted a slight
but noticeable hum. At this level the test system registered at 22 dBA which
was rather low, but the type of noise was unpleasant. The stock cooler cooled
the card admirably, though at a noise level few could tolerate. Let's see
what the VF1000 can do.

B. Zalman VF1000 LED

Zalman VF1000 LED Test Results

State

Fan Speed

GPU Temp

VGA Ambient

CPU Temp

AC Power

System Noise @ 1m

ATI Tool

12V

73°C

54°C

42°C

248W

30 dBA

ATI Tool

9V

76°C

56°C

43°C

249W

28 dBA

ATI Tool

7V

78°C

57°C

43°C

248W

24 dBA

ATI Tool

5V

79°C

58°C

43°C

248W

21 dBA

Idle

5V

46°C

39°C

26°C

124W

21 dBA

Note: the stock memory heatsink was used

@12V: The noise was very high pitched and whiney. Cooling performance
was incredible with both the GPU and surrounding environment a good dozen
degrees lower than the stock cooler.

@9V: The pitch of the overall sound dropped somewhat but high
turbulence kept the noise level intolerable. Performance dropped off by
a few degrees.

@7V: The fan exhibited some unpleasant undertones but it was hard
to detect as turbulence was dominant. At 2°C higher than 9V, the GPU
was still fairly cool.

@5V: At 1m, the fan was basically indistinguishable from the rest
of the noise emanating from the system. Performance was still very good
at 79°C  only 1°C higher than at 7V. In addition it was
much quieter than the stock heatsink yet 6°C cooler.

Overall, these are very impressive results with only 6°C separating
the 5V temperatures from the 12V temperatures. At 5V it's clear the VF1000
cooled the X1950XTX better than the stock cooler with only a small amount
of airflow without adding any noise to our already quiet test system.
System power consumption also dropped a few watts, possibly because the
video card fan was powered externally. The older VF900-CU has a tough
act to follow.